Richard dormer



UNITED STATES PATENT OFFIC 1 RICHARD DORMER, OF GARSTON COUNTY OF LANCASTER, ENGLAND.

OBTAININ G CHLORINE.

SPECIFICATION forming part of Letters Patent No. 427,467, dated'May 6, 1890,

Application filed April 29, 1889. Serial No. 303,951. (No specimens.)

To all whom it may concern: 7

Be it known that I, RICHARD DORMER, F. C. 8., a subject of the Queen of Great Britain, residing at Garston, in the county of Lancaster, in the Kingdom of England, have invented certain new and useful Improvements in Obtaining Chlorine, of which the following is a specification.

111 the ordinary process of obtaining chlorine by acting upon manganese dioxide (M110 with hydrochloric acid, (E01,) onehalf only of the chlorine (C1) in the hydrochloric acid (H01) used is by theory evolved, the other half remaining in solution as manganese chloride, (Mn0l Thus;

(I) MnO +4H0l=MnClg-l-Cl -l-2H O. By this invention I propose, first, to obtain the Whole of the chlorinein the hydrochloric acid (H01) by taking advantage of the fact that in the presence of sulphuric acid (H 80 hydrochloric acidtIIOl) acts upon the manganese dioxide (M110 according to the following reaction:

2 MnO +2H0l+H SO =2Cl+MnSOi+2H:O, v and thus theoretically producing the Whole of the chlorine contained in the hydrochloric acid, (HOL) In the ordinary process the 1nanganese chloride (M1101 formed by Reaction 1 is treated by thelVeldon or Dunlop process, in order to recover the manganese in the state of manganese dioxide. By my process the whole of the chlorine is obtained ac cording to Reaction 2, and the manganese (Mn) is produced in the state of manganese sulphate, (MnSQ which in this condition is wholly unsuitable for recovery as manganese dioxide (M110 by either the \Veldon or Dunlop process.

By this invention I propose to convert the manganese sulphate (M1180 into manganese chloride (M1101 by the addition of a solution of calcium chloride (OaCh) in excess, as shown by the following reaction:

' the calcium chloride (0a0l for this purpose settling or filtering from the calcuim sulphate, (021 804,) and is then in a suitable condition to be treated for the recovery of the manganese or Dunlop process, as at present. The loss of manganese in recovery can be supplied by dissolving native manganese dioxide or pyrolusite (M110 in hydrochloric acid (H01) in the ordinary Way, the solution thus produced being neutralized in the ordinary manner by addition of chalk or other calcium carbonate (CaCO or other suitable agent, this neutral manganese chloride (M1101 being added to the solution of MnCl as formed by Reaction 3.

From the foregoing description of this invention it Will be seen that the various reac tions involved are as follows:

(i)MnOH-ILSO.i+2H0l:20li-M11SO4+2HQO. 2 Mnsoi+cae1,=1uncn+cas0,. (3) Mn0lg+lime+air l/veldon mud-i-CaCh. Reaction 1.This may be Worked in the usual stone stills or in a suitably-shaped iron still lined with lead, brick, or such material as may be found most suitable, the heat being supplied by steam or direct heat, as may be found most suitable for the apparatus used; the manganese dioxide (MnO or Weldon mud, as the case may be, being supplied with aquantity of sulphuric acid (H SO,,) sufficient to convert the Whole of the compounds present into sulphates, and the hydrochloric acid (H01) being added in slight excess over and above the amount equivalent to the available oxygen of the manganese dioxide (M110 or WVeldon mud employed, thus preventing any extra loss of manganese in comparison With the usual method of dissolving in hydrochloric acid (1-101) alone, While the sulphuric acid (11 0 is kept at its lowest possible limit necessary for the above purpose of converting the said compounds into sulphates.

Reaction 2. part of the process the product from the stills after generation of the chlorine (as shown in Reaction 1) is neutralized by chalk or other suitable material in a convenient vessel and chloride of calcium then added in sufficient excess to convert the Whole of the manganese into chloride, (Mn0l leaving enoughcalciuxn chloride Ja0l in solution for the satisfactory as manganese dioxide (M110 by the Weldon Before proceeding with this working of the usual eldon process of recovery; but in the case of the Dunlop an excess is not necessary. The calcium sulphate (CaSO is allowed to settle and the supernatant manganese chloride (M1101 run to the stock-tanks ready for the recovery. The calcium sulphate (OaSO is either washed by d ecantation with calcium-chloride (CaOl solution or water, (11 0,) as maybe found most convenient; or it may be filtered through a filterpress or other suitable separator and washed in order to cleanse it from the manganese solution. The calcium sulphate (CaSOQ could be dried and usedfor any convenient purpose. The manganese is now in solution as manganese chloride, (MnOl and consequently suitable for the recovery of the manganese by the usual method of WVeldon or Dunlop, as at present, by means of lime or chalk, respecti vely.

From the foregoing description of this process it will be seen that in order to obtain the whole of the chlorine in the hydrochloric acid (H01) used the only extra cost of material is that of the sulphuric acid, (11 80 In the ordinary process the chlorine produced is theoretically fifty per cent. of the amount contained in the HCl, while the various practical losses in the production of bleaching-powder or chloride of lime reduce the practical production to about one-half the theoreticalequal to a loss of, say, twenty-five per cent. of the chlorine.

By this invention the chlorine produced is theoretically one hundred per cent. of the amount in the 1-101, and taking the same practical loss as before-namely, twenty-five per cent.the practical result is, say, three times that of the ordinary process.

I claim as my invention-' 1. The process of obtaining chlorine which consists in forming an aqueous mixture of sulphuric acid, hydrochloric acid, andmanganese dioxide, (or WVeldon mud,) and separating the chlorine, neutralizing, adding calcium chloride in excess to the aqueous residue, and thereby throwing down calcium sulphate, separating the latter, and treating the remaining solution of manganese chloride and calcium chloride with chalk or lime to form WVeldon mud, substantially as described.

2. The improvement in the process of obtaining chlorine which consists in adding to the manganese dioxide or Weldon mud half the usual amount of hydrochloric acid used in the WVeldon process, and also sufficient sulphuric ,acid to convert into sulphates all the compounds of manganese and lime present, and then adding sufficient chloride of calcium to reconvert the sulphate of manganese into chloride, substantially as described.

3. The improvement in the process of 0btaining chlorine and sulphate of lime which consists in adding to the Weld on mud only half the usual amount of hydrochloric acid and supplying the deficit With sulphuricacid and calcium chloride, collecting the chlorine which comes off, separating the chloride-of-manganese solution from the precipitate, whereby the whole of the chlorine in the hydrochloric acid is obtained in a useful form and an exceedingly pure and fine-grained calcium sulphate is obtained, substantially as described. I11 testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

RICHARD DORMER. Witnesses:

CORNELIUS Horn, WM. P. THOMPSON. 

